TODDLERS SPEECH AND COGNITIVE EFFORT

Two-year-olds were videotaped while engaged in free play and problem-s olving play. The periods in which they were actively manipulating obje cts were analyzed as to level of engagement, distinguishing between pe riods of intense engagement, in which the children were concentrating on the nonverbal activity, and periods of casual engagement, in which they conducted the nonverbal activity in a more leisurely fashion. A m icroanalysis of the children's spontaneous speech revealed that they s poke less at moments of intense engagement than at moments of casual e ngagement. These and other findings are taken as support for the hypot hesis that when toddlers invest cognitive effort in nonverbal behavior , there is a reduction in mental resources available for speech.